Water repellent packing material



Sept. 4, 1934. c, GOTTWALD WATER REPELLENT PACKING MATERIAL AND CONDUITOriginal Filed Aug, 12

' l N VEN TOR.

A TTORNEYS Reissued Sept. 4, 1934 UNITED STATES WATER REPELLENT PACKINGMATERIAL AND CONDUI'I' Christian Gottwald,

Cleveland Heights, Ohio, as-

signor to The Ric-Wil Company, Cleveland, Ohio, a corporation of OhioOriginal No. 1,801,500, dated April 21, 1931, Serial No. 212,502, August12, 1927.

Application for refssue August 8?.1931, Serial No. 556,038

4 Claims.

. The present invention relates to an improvement in underground conduitsystems, in which a pipe or pipes for conveying a liquid 'or gas arehoused within an enveloping structure of metal, o tile, concrete orbrick.

The invention has particularly to do with the matter of packing forsurrounding the pipe or pipes within the housing or envelope, thepacking having the peculiar property of repelling 10 water, so that thesame will not become watersoaked, and thus breakdown its quantities as athermo non-conductor.

Reference should be had to the accompanying drawing forming a part ofthis specification, in

which the figure shows, in cross section, a well known form ofunderground conduit construction with the thermo non-conducting packingsurrounding the enclosed pipe.

In the drawing, 1 and 2 designate the upper and lower portions of a wellknown form of conduit, usually made of vitreous material. A well knownform of base drain is indicated at 2.

Within the conduit is a pipe 4 for fluid conducting purposes, which pipeis supported upon supports 5 which are of a well known commercial form.

Surrounding the pipe and confined within the conduit is the thermonon-conducting packing material to which reference is made later on inthis specification.

0 Underground conduit systems are prone to have moisture accumulatewithin the outer casing or conduit, either because of moisturecondensing, or in some instances from the ingress of water from theoutside.

It is usual in underground conduit systems to provide some sort ofdraining feature, both to drain water from the surrounding earth inwhich the conduit is placed, and also to provide suitable vents or meansby which water that may accumulate or find its way into the conduititself may be drained.

In underground conduit systems where the pipe or pipes are conveying aliquid or gas which i 5 is either above or below the normal temperature,

as for instance steam, or on the other hand a refrigerant gas or fluid,it is necessary to enclose and pack the pipe or pipes with some suitablenon-conductor of heat. The diificulty has been that the usual forms ofthermo non-conductors become impregnated with water or moisture, andthus decrease, and with the accumulation of sufficient moisture breakdown the thermo nonconductivity of the packing. The usual packings whichhave heretofore been employed, such as shredded asbestos, rock wool andmineral wool are in each instance comprised of siliceous fibers which ofthemselves are water proof. These substances being crystalline instructure and not cellular will not absorb water, so that they may beproperly described as water-proof. However, when these substances areused as packing materials in underground conduit systems, the waterwhich condenses within the conduit or finds its way into the conduitfrom outside sources will 66 nevertheless soak the fibrous mass, thewater finding its way into the interstices between the fibers and therebeing held, and upon a sufiicient accumulation of water the thermonon-conductivity of the packing mass is impaired or destroyed. 70Apparently the water penetrates into the mass of fibers by capillarityand lodges in the interstices between the fibers, and this will occureven though-care is taken to sufiiciently pack the libro'us mass so asto avoid. leakage or appreciable pockets in the packing.

The present invention has to do with a packing material, which, bytreatment, is rendered water repellent, and by this is meant that watercoming in contact with a mass of fibers is repelled, so that the waterdoes not find its way into the interstices between the fibers.

More specifically speaking a fibrous packing material, such as shreddedasbestos, rock wool, mineral wool or equivalent material which in usualcommercial form is unmatted and having loosely associated fibers which,in itself, is waterproof, is treated by chemicals so as to render thefibers water repellent, and when a mass of unmatted, loosely associatedfibers of material so treated is loosely packed around a pipe or pipeswithin a conduit, the density of the packing being such as to avoidappreciable sized pockets or spaces in the packing, water coming incontact with the mass of fibrous material will be repelled and the waterwill run down the inner wall of the enveloping conduit to be dischargedthrough the usual base drain. The effect of the treatment given to thefibers of the fibrous material seems to be in effect to break down theusual capillary action, by which water might ordinarily be drawn intothe interstices between the fibers, and by virtue thereof the water isrepelled. Whether the foregoing be the correct explanation of thephenomena is not important, but the fact that the fibers are renderedrepellent to water is important.

The fibrous material may be treated to render it water repellent byvarious substances, one of which may be mentioned, being aluminumstearate which chemically is lcnown as an insoluble soap, as set forthin a book entitled "Soaps" by Geo. H. Hurst (3rd edition) at page 18,and a book entitled "Industrial and Manufacturing Chemistry" (6thedition) by Jeffry Martin, page 101.

I am aware that it has been heretofore proposed to treat certainmaterial which is cellular in nature in order to make it water-proof,but my invention diflers from such procedure in that it makes thefibrous material treated water repellent.

Merely being w ter-proof is not suiflcient for, as before pointed out,asbestos, -rock wool and mineral wool are all inherently water-proof,but nevertheless a fibrous mass oi these materials will watersoak by theaccumulation of water in the interstices between the fibers.

It is only by making the flbers water repellent so that water will notaccumulate in the interstices between the flbers, that an efllcientpacking for underground pipes which are housed in conduits can beobtained.

Having thus described my invention what I claim as new is:

1. The combination with a conduit having drainage means and a fluidconducting pipe therein,- of a mass of thermo non-conducting materialcomprising a mass of unmatted and comparatively loosely associatedmineral fibers coated with material which renders them water repellent,surrounding said pipe and within the conduit.

2. The combination with a conduit having drainage means and a fluidconducting pipe therein, of a mass of thermo non-conducting materialcomprising a mass of unmatted comparatively loosely associated asbestosflbers coated to render them water repellent surrounding said pipe andwithin the conduit.

3. The combination with a conduit, of a pipe extending through saidconduit and adapted to conduct fluid, and unmatted water repellentfibrous mineral material loosely compacted within said conduit andclosely surrounding said pipe.

4. The combination with a conduit, of a pipe extending through saidconduit and adapted to conduct fluid, and a mass of unmatted asbestosfibers rendered substantially water repellent in bulk and looselycompacted within said conduit to entirely surround said pipe.

